I don't think there is anything in tank that will help. My thoughts would be to spray something like b-12 throught the intake while it was cold and being cranked, and let it sit a bit. Then crank it up after say 5-10 minutes and spray more through the intake. The problem is, you would have to do this on a regular basis to really have any effect.

Supposedly a PEA-based cleaner will linger around a little while after combustion and dissolve some of the carbon. If a strong enough dose is used, and if the engine programming allows for enough overlap where the intake valves are open while the exhaust valves are open. Supposedly...

The best way is using a low NOACK oil and a good old-fashioned Italian tuneup once a week or so. Get that engine and those valves hot.

DI is probably not a good idea for the person that keeps a car beyond the factory warranty. In fact owning any Audi beyond the warranty might get expensive, very expensive. One neighbor just spent $2,800 on an Audi timing belt, water pump and seals. A few years ago another neighbor bought a used car for $2,500 and drove it for 25K miles commuting to work with nothing more than oil changes and gasoline. He hit the roof when he had to spend $400 on the same kind of timing belt/water pump service. Much of this new technology and gadgets are for the first owner that ditches the car just before the expiration of the warranty. These fancy cars will not survive long after the first major glitch. A local shop here has half a dozen of these fancy cars in the back lot waiting for the customer to pay or for the recycle tow truck to show up because they are not worth the cost of repairs.

These additives will help prevent/reduce but they will not help clean. The engine is a system and the additives mainly help with the injectors and combustion chambers parts of this system. This in turn will help prevent/reduce DI deposits.

If injectors foul (and DI injectors do foul), you don't get as good of combustion. This leads to more gas making it into the oil. Gas in the oil increases volatility which increases PCV vapors that condense and deposit on the intake valves.

Regular fuel system cleaners is the first line of defense against intake valve deposits.

Afton Chemical claims to have a detergent additive designed to clean DI engines. However, they're one of the major additive makers and it's specifically designed for treating bulk fuel. I suppose some treatment in a bottle marketer could buy it and bottle it for the aftermarket.

Afton Chemical announced a new gasoline additive developed to clean and prevent deposits in Direct Injection Gasoline (DIG) engines. With car and truck manufacturers rapidly embracing DIG technology, the additive will be a robust remedy for an imminent problem. Our new technology keeps DIG injectors clean and it also offers our customers industry leading LAC and TOP TIER™ treat rates.

According to Dave DiBerto, Global Fuels Business Manager for Afton, “DIG engines can be prone to performance-robbing deposits that form in fuel injectors.” DiBerto said, “In a DIG engine, the fuel injector is located directly in the combustion chamber. This is intended to improve fuel economy and power, but the thermally-harsh environment can cause deposits that clog fuel injection ports and actually reduce performance.”

I believe the issue would be that it's not sprayed directly onto the intake valves. The mist is a great way to get the valve soaked in the fuel/detergent mix. So whatever cleaning action would have to come from whatever tiny amount of mist gets onto the valve before the whole mixture explodes. I've heard that some DI engines come with small port fuel injectors to make up for the lack of cleaning. It still gets the major benefits of spraying directly into the cylinder, but takes care of one of the issues.

Afton Chemical claims to have a detergent additive designed to clean DI engines. However, they're one of the major additive makers and it's specifically designed for treating bulk fuel. I suppose some treatment in a bottle marketer could buy it and bottle it for the aftermarket.

Afton Chemical announced a new gasoline additive developed to clean and prevent deposits in Direct Injection Gasoline (DIG) engines. With car and truck manufacturers rapidly embracing DIG technology, the additive will be a robust remedy for an imminent problem. Our new technology keeps DIG injectors clean and it also offers our customers industry leading LAC and TOP TIER™ treat rates.

According to Dave DiBerto, Global Fuels Business Manager for Afton, “DIG engines can be prone to performance-robbing deposits that form in fuel injectors.” DiBerto said, “In a DIG engine, the fuel injector is located directly in the combustion chamber. This is intended to improve fuel economy and power, but the thermally-harsh environment can cause deposits that clog fuel injection ports and actually reduce performance.”

I believe the issue would be that it's not sprayed directly onto the intake valves. The mist is a great way to get the valve soaked in the fuel/detergent mix. So whatever cleaning action would have to come from whatever tiny amount of mist gets onto the valve before the whole mixture explodes. I've heard that some DI engines come with small port fuel injectors to make up for the lack of cleaning. It still gets the major benefits of spraying directly into the cylinder, but takes care of one of the issues.

Afton Chemical claims to have a detergent additive designed to clean DI engines. However, they're one of the major additive makers and it's specifically designed for treating bulk fuel. I suppose some treatment in a bottle marketer could buy it and bottle it for the aftermarket.

Afton Chemical announced a new gasoline additive developed to clean and prevent deposits in Direct Injection Gasoline (DIG) engines. With car and truck manufacturers rapidly embracing DIG technology, the additive will be a robust remedy for an imminent problem. Our new technology keeps DIG injectors clean and it also offers our customers industry leading LAC and TOP TIER™ treat rates.

According to Dave DiBerto, Global Fuels Business Manager for Afton, “DIG engines can be prone to performance-robbing deposits that form in fuel injectors.” DiBerto said, “In a DIG engine, the fuel injector is located directly in the combustion chamber. This is intended to improve fuel economy and power, but the thermally-harsh environment can cause deposits that clog fuel injection ports and actually reduce performance.”

I believe the issue would be that it's not sprayed directly onto the intake valves. The mist is a great way to get the valve soaked in the fuel/detergent mix. So whatever cleaning action would have to come from whatever tiny amount of mist gets onto the valve before the whole mixture explodes. I've heard that some DI engines come with small port fuel injectors to make up for the lack of cleaning. It still gets the major benefits of spraying directly into the cylinder, but takes care of one of the issues.

Afton was specifically talking about DI injectors.

The quote might have been the wrong one to use. I was thinking more of the HiTEC-6470.